Numerous freestanding desks or tables as utilized in offices and educational environments are provided with height-adjustment capability, including use of mechanisms which employ a manually-actuated rotatable crank for activating a drive element such as a drive shaft or flexible element which in turn cooperates with height-adjusting units associated with the legs. In many of the known height-adjusting arrangements, the crank is often supported for connection to a driving member at a position under the worksurface, whereby the operator must access the crank to effect rotation thereof, and often times accessing the crank is difficult or inconvenient because of its location under the worksurface.
In other known desks or tables, attempts have been made to overcome the above disadvantage by providing a drive member which projects up and is accessible from above the worksurface. Such arrangements have typically provided a drive hub at or above the worksurface, and in such case a removable crank is provided which must be separately stored, then engaged with the drive hub when height adjustment is desired, and then removed and restored. Such arrangement has also proven undesirable, however, in that provision of a separate and removable crank is inconvenient since often times there is no convenient place to store the crank, so that the crank can be easily misplaced and this thus makes height adjustment inconvenient due to the necessity of having to continually retrieve the crank from storage for use, and then restore the crank.
It is an object of this invention to provide a freestanding height-adjustable table or desk having a height-adjusting mechanism which employs a manually activated crank, which crank can be accessed and operated from a location above the worksurface, but which can be folded and stored in a recess which is substantially flush with the upper surface of the worksurface, whereby the crank remains permanently connected to the drive arrangement at all times.
In the freestanding desk or table of this invention, the worksurface is supported on height-adjustable legs, each having a height-adjusting mechanism which in the preferred embodiment comprises an extendable and contractible screw unit. The screw units associated with the legs are simultaneously driven through a driving element such as an endless chain which is driven by a driving sprocket disposed adjacent the underside of the worksurface. The driving sprocket is nonrotatably connected to a rotatable hub which is supported in a recess in the worksurface, which recess also accommodates a foldable crank. The crank when in a folded and stored position is disposed in the recess so as to be substantially flush with the upper surface of the worksurface. The crank can be pivoted upwardly about a first axis and is pivotally joined about the first axis to an intermediate link which in turn pivots about a second axis to a rotatable hub so that the crank can be pivoted upwardly through an angle of about 180.degree. so as to be disposed above the worksurface to permit manual gripping and hence rotation thereof when height adjustment is desired.
Other objects and purposes of the invention will be apparent to persons familiar with structures of this general type upon reading the following specification and inspecting the accompanying drawings.